Field of the Invention
The invention relates to a housing for receiving a component which can be connected to the housing in a pluggable manner, in particular an optoelectronic transceiver.
It is known to arrange optoelectronic transceivers on a printed-circuit board and connect them to an optical network by means of optical plug-in connectors. Known in particular are so-called small-form-factor-pluggable (SFP) transceivers of a small type, which are of a pluggable design (so-called xe2x80x9cdetachable transceiversxe2x80x9d) and can be plugged into a receptacle of a housing mounted onto the printed-circuit board.
A corresponding housing 1 is represented in FIG. 5. The housing comprises an upper part (top cage) 22 and a lower part (bottom cage) 21, which can be connected to each other in an engageable manner and form a receiving housing into which a transceiver can be plugged or from which a transceiver can be unplugged in the direction of the double-headed arrow A-B. At the same time, the housing 1 preferably serves as a shielding plate for the electromechanical shielding of the pluggable transceiver.
The lower part 21 of the housing is fastened on a printed-circuit board 3. Both parts of the housing 21, 22 protrude through a cutout in a metallic rear wall (not represented), which is electrically connected to the housing via contact springs 11. Also mounted within the housing and directly on the printed-circuit board 3 is an electrical plug 4, by means of which the plugged-in transceiver can be connected to the printed-circuit board 3 and into which the transceiver is inserted during plugging into the housing 1.
During plugging of a transceiver into the housing 1, rectangular pressing springs 51, 52 formed in the region of the rear end face of the lower part 21 of the housing are prestressed. Locking of the transceiver in the housing takes place by means of a locking clip 6, which is formed in the front region of the lower part 21 of the housing and into which a locking lug of the transceiver can engage. During unlocking of the transceiver by pressing down of the resiliently formed fastening clip 6, the transceiver is pressed out of the housing 1 by the prestressed pressing springs 51, 52. The rectangular ejecting springs 51, 52 are represented in front view in FIG. 6.
A disadvantage of the known housing is that the spring forces achieved by stressing of the pressing springs 51, 52 are not adequate to ensure in a dependable way that the transceiver is pressed out of the housing 1 when it is unlocked. In particular, the transceiver is pressed only a small distance out of the housing on account of frictional forces between the housing and the transceiver during unlocking.
The present invention is based on the object of providing a housing for receiving a component which can be connected to the housing in a pluggable manner which ensures that the component is dependably and reliably pressed out of the housing when it is unlocked.
Accordingly, it is provided according to the invention that at least one pressing spring of the housing is designed in such a way that it tapers in its width in the direction of the interior of the housing. A spring form of this type has the advantage that higher spring forces can be realized with it: the restoring force or spring force is greater than in the case of a rectangular design of the pressing spring known in the prior art. This results from a more uniform bending stress of the spring material which accompanies the reduction in the width of the spring in the direction of the interior of the housing. In particular, the tapering spring bends in a form approximating that of a circle, while a rectangular spring bends in the form of a parabola. However, circular bending entails a higher amount of spring work and energy storage.
A further advantage of using a spring tapering in its width is that less space is taken up by the spring inside the housing. One result of this is the possibility of extending the length of the spring in the direction of the interior of the housing, allowing for example the end of the spring to protrude beyond an electrical plug arranged in the housing. By extending the length of the spring, higher spring forces can also be realized. Another result is the possibility of making an electrical plug arranged in the housing or other components arranged in the housing larger and consequently easier to handle.
In a preferred development of the invention, the pressing spring is of a trapezoidal design. The two parallel sides of the pressing spring in this case run parallel to the lateral walls of the housing. On account of the tapering of the pressing spring in the direction of the interior of the housing, the parallel side running in the interior of the housing has a smaller width than the side running along the wall of the housing. A trapezoidal design of the spring has the advantage that it is simple to produce, since the corresponding edges of the metal plate can be worked in straight lines.
It is likewise within the scope of the invention for the pressing spring to be of a triangular or else parabolic design. In the case of a triangular design, it is preferred to provide the form of an isosceles triangle, the base of which runs along the wall of the housing and the corner of which, formed by the equal sides, lies in the interior of the housing. Similarly, in the case of a parabolic design of the pressing spring, the inflection point of the parabola lies in the interior of the housing.
In the preferred embodiment, the pressing spring is designed as a rear continuation of the plate of the housing, with respect to the plugging-in direction of the component, bent around by more than 90xc2x0 into the interior of the housing. This is a simple way of providing an integral design of the spring with the housing which can be easily produced.
The housing is preferably designed in such a way that it has an upper part and a lower part, which can be connected to the printed-circuit board. The pressing spring is in this case preferably articulated on the lower part.
Preferably, two pressing springs are articulated on the right-hand and left-hand walls of the housing in a symmetrical arrangement, to be precise in each case in the upper region of the wall of the housing. This ensures that the pressing springs are freely accessible and are not concealed by other components arranged in the housing, such as a plug connected to the printed-circuit board.
The legs of the pressing spring articulated on the housing preferably terminate flush with the upper edge of the housing. This provides a maximum size of the spring toward the upper edge of the housing.